The backers of an effort to expand Georgia's medical marijuana program won't be able to rely on support from the nation's top farm official.

Former Gov. Sonny Perdue, now Donald Trump's agriculture secretary, said a measure that would allow farmers to cultivate medical marijuana in Georgia is "against federal law" and indicated he would oppose the effort.

"The fact is I think it's a very slippery slope how you enforce," he said, adding: "As governor, I was always aware of the federal supremacy law, which meant that federal law preempted state law when when it spoke."

Georgia has steadily expanded its medical marijuana program to cover more illnesses, but it remains illegal to grow the plant in Georgia. State Rep. Allen Peake and other supporters of an expansion have sought ways to allow patients to legally obtain the drug in the state.

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